Audiophilleo AP2+PP vs iFi iUSBPower+Gemini cable

Hi everyone,

I'm from Indonesia and this is my 1st post so please excuse my English and "review" quality.

Reviewed objects: Audiophilleo AP2+PP vs iFi iUSBPower+Gemini cable

Source: Sony VAIO VGN- Z48GD laptop using USB output, Intel Core Duo CPU P9700 @2.80GHz, 6GB RAM, 256GB SSD Hardisks, OEM sound card, Win7 64bit
Music Player: JRMC 18 (WASAPI, DSP off, Gizmo remote app)
Ripper: dbPoweramp, DVD Audio Extractor, JRMC 18
Amp: norma REVO IPA 140 integrated (2x280W driving 4ohms speakers)
Speakers: Dynaudio Confidence C1 MKII Signature on Dynaudio unfilled Stand 4
Cables & IC: WireWorld Ultraviolet USB for all USB connections, unbalanced RCA IC (DIY cable with OFC copper, pure silver coated OFC copper strands, 24 carrat gold coated OFC copper strands, mid-end RCA gold plated connectors) from NAD M51 unbalanced output to unbalanced norma's input, Clear Day Double Shotgun speaker cables.
Converter & DC filter: Audiophilleo AP2+PP as USB/SPDIF converter and iFi iUSBPower+Gemini cable as USB power both connected to their appropriate input to NAD M51 DAC.
Electrical: regular house wiring, no AC filtration, OEM AC chords/adaptors.
Room treatment: none
Sound processor: none
Room: approximately w/l/h 7.5x5x3.45(m). It is my bedroom :)
Music files: WAV 16/44.1 24/88.2 24/192 (no down/upsampling in JRMC, ripped from my own Redbook CDs, DVD-AudioS, HDtracks, Blue Coast Records (DSF converted to 24/192 WAV with JRMC) downloads.
About myself: not an audiophile, can not sing nor play any instrument, no EE background, only 6 months ago started to own a decent home audio system, so far has not auditioned many home audio gears but had listened to low-end AVR based system to top of the line full AudioNote sytem to MBL systems, turntables system with high end tubes McIntosh gears, and various mid-high end active, pasive speakers from mini monitors to big floor stander such as, B&W Nautilus, Alcapela, Sonus Faber Aida, etc. All auditions were done in demo room of authorized dealers. I'm a newbie in home audio, I had some experiences in car audio from 1994-2008 as a competitor in SQ competition events sanctioned by IASCA USA (amateur class) and a major event in Indonesia (pro FFA analog class). Extensive experiments in car audio gears modification (done by modificators, not me) and reviewing highly modified analog & digital car audio gears including speakers.

Now that you know where I come from, this time I tried to compare the sound of AP2+PP (approximately US$1000) with IUSBPower+Gemini USB cable (approximately US$500) in my system and using my own ears only. No other listener was present. From price, connection types and technology stand points clearly that was not exactly apple to apple comparison and YMMV. My only understanding is these devices were made to improve the sound comming out of my DAC from sources using USB output and I wanted to know do they work as advertised and which one is better. And this is what I found:

Both Audiophilleo AP2+PP and iFi iUSBPower+Gemini cable sounded much better in all factors than direct connection from my laptop to NAD M51's USB input. The improvement were easily heard even for 16/44.1 musics. With higher bit & freq files the differences were even more audible. With any songs I needed only a few seconds to draw a conclusion. Not that NAD M51 sounds bad at all (I would not purchased it in the first place if I thought it was not good) but those two devices for sure remarkably improved my NAD M51's sound.

Now which one is better and how big is the differences between these two devices?
In summary, AP2+PP is SLIGHTLY better than iUSBPower+Gemini cable. The differences with acoustic music and vocals were so subtle though. I was forced to play the same songs repeatedly to pint point the differences even needed to turn off my room air conditioner when listening to highly dynamic musics to capture differences in ambience and low volume micro details. With electronic music with lots of low bass such songs from Daft Punk, quality of bass extention was more easily audible in favor of AP2+PP.

Bellow is my "more detailed" review using only a few songs (actually during the review I listened to much more songs from different genres but these few songs are enough to represents my finding). Please note I didn't look for same sonic parameters in all songs. I only focused on certain things that I thought was important for certain songs/genre i.e., when listening to classical music I look for fluidity, dynamic, timbre, staging, layers, noise during quite passage, etc. While listening to solo guitar+vocal or other small jazz/blues bands I look mostly for timbre, perceived naturality (whether it is true or not I certainly have no idea since I wasn't in the recording studio), grain, micro details, air around instruments and singer, clarity, transient, etc. For other musics I might focused only on highs smoothnes, sybilance, mids coloration, bass extension, PRAT, etc. If I don't mention some of those parameters such as PRAT, grain, etc then that means both devices were on par.

I strated with I Bid You Goodnight from Aaron Neville's Warm Your Heart (16/41). This wasn't a high quality recording but I found it useful to tell sound characters of different gears. Simply transparent, detailed and high resolving gears will unmasked the imperfection in this recording. Sound will be thin, lean, weak bass extension, harsh and esdgy highs with excessive sybilance. While better gears with same characteristics (transparent, clear, detailed, etc) will still show those imperfections but with more refinement with resulted in more musical and less fatiquing sound.
iUSB+Gemini: Cymbal was clear without harshness and edginess, nice texture with good decay. Neville's vocal was a little bit veiled and a had little less body than I prefer. Listening to drum bass sound, while mid bass had good impact, it was more dominant which resulted in more "thud" than "thump" with less reverberation. I felt lthe bass wasn't extended enough as if there was a 12db 50Hz high pass XO in placed. This might sound like a bad review of iUSB bass quality but I have to tell you the bass sound was still very very good compare to direct USB connection. There was no contest here. The drum bass had good natural skin texture, tight impact and way more extended compare to direct connection.
AP2+PP: Cymbal sounded similar to iUSB but with denser texture, more airy and longer decay. Neville's vocal was clearer and seperation from bass vocalist and back singers were subtly more defined. Drum bass I think both had the same texture density, tighness but the low freq extension was better with more reverb and natural roll off resulted in rounder more coherent bass freq. In other words the AP2's bass was more enjoyable to my ears.

Lose Yourself to Dance. From Daft Punk's Random Access. Memory (24/88.2)
iUSB+Gemini: clear highs and extended not harsh in any way. Vocal exhibited no sybilance, clear, unnatural with high resonance peak around 650-800Hz that almost hurt my ears (probably because vocal was intentionally heavily processed to suit better with the rest of synthesized sound). Bass: extended, full, strong, good impact and good reverb.
AP2+PP: highs only very slightly less bright and easier to distinguish each high freq sounds coming from whatever instrumens or sound from sound bank. Vocal also unnatural with the same annoying freq peak mentioned above. Bass lost a little thud compare to iUSB but again AP2 had lower and stronger extention.

The Firebird Suite from McIntosh DVD-Audio Spectacular Reference Disc (2 ch 24/96).
iUSB+Gemini: Staging was high, wide, good depth, instrument seperation, layer, placement were very good. Mid+High: clear, clean, nice timbre, dense texture, instruments sounded natural and believably real in size, music flowed fluidly with good dynamic.
AP2+PP: Staging: same height, but definitely deeper, at least the same width Mid+High: only a little bit more natural, less edgy, brass instrument (timbre) sounded closer to real thing. Bass: again fuller and more extended.

Duo For Violin and Cello op.7 from same McIntosh DVD-A
Ap2+Pp: violin very fluid, very good micro detailed, sound from cello's hollow body easily heard, fast transient, unmistakably cello sound!
iUSB+Gemini: had all of the above AP2 quality but with SLIGHTLY less of everything.

After reading my comments you might think I prefer AP2+PP over iUSB+Gemini cable. Well you are both right & wrong. If I ONLY using USB input on my NAD M51 given the price differences (half) and great sound quality of iUSB+Gemini, I prefer to buy the iUSB+Gemini cable. But in my case since I also use Synology NAS with Linux OS which unfortunately NAD M51 doesn't provide Linux driver, I need AP2 (which is compatible with Linux) to connect my NAS (not used for this review) to NAD M51 using it's SPDIF coaxial input. I was hoping iUSB+Gemini cable would deliver un distinguished able sound, unfortunately/fortunately I found AP2+PP was a little better but it came with double the price.

Both are highly recommended devices.

Now would someone kindly tell me how to attach pictures to this posting, add tags and add signature? Tqb4.

Very nice review. Well done
Mr Narukama,

Thanks for your most excellent evaluation. I am in exactly the same position trying to figure out how to improve my M51 when it is fed from a computerized source.

I just wanted to let you know I am going to get the iUSB based on reports from you and others. I was wondering though, did you try the iUSB with other good quality USB cables instead of the Gemini? If so can you comment on this?I have read people having mixed feelings on the Gemini compared to more conventional good quality cables.

As an aside, if I had the money I would spring for the NAD M50 network player which is supposed to be magical when feeding the M50 through the AES input. But at US $2500 it's a bit steep.

The AP can also be improved by using Connectronics brand BNC / RCA adapters in lieu of those provided with the AP unit. The Connectronics sound much better and are very inexpensive from Markertek. They are sometimes listed as TecNec brand made by Connectronics. If you need the adapters for connection, they make a huge SQ difference for for less than $10. If you already own the AP, you have not heard it until you upgrade the adapters. They look nearly identical to the ones AP provides but have less ferrous metal as they have far less attraction to a magnet. Almost none. No affiliation with BTW.

I also found a good coax cable sounds better between the DAC and AP than direct connection of the AP to the DAC. I use the BlackCat Silverstar myself, with excellent results.
Same thing as Hightechred, The AP1 sounds a lot better with a coaxial cable between the AP1 and the DAC than a direct connection, even using AP1 virtual cable settings. I use naim DC1 1.25m with very good results.